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It is difficult to establish the properties of massive stars that explode as supernovae. The electromagnetic emission during the first minutes to hours after the emergence of the shock from the stellar surface conveys important information about the final evolution and structure of the exploding star. However, the unpredictable nature of supernova events hinders the detection of this brief initial phase. Here we report the serendipitous discovery of a newly born, normal type IIb supernova (SN 2016gkg), which reveals a rapid brightening at optical wavelengths of about 40 magnitudes per day. The very frequent sampling of the observations allowed us to study in detail the outermost structure of the progenitor of the supernova and the physics of the emergence of the shock. We develop hydrodynamical models of the explosion that naturally account for the complete evolution of the supernova over distinct phases regulated by different physical processes. This result suggests that it is appropriate to decouple the treatment of the shock propagation from the unknown mechanism that triggers the explosion.
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This review aims to showcase the brachytherapy tools and technologies that have emerged during the last 10 years. Soft-tissue contrast using magnetic resonance and ultrasound imaging has seen enormous growth in use to plan all forms of brachytherapy. The era of image-guided brachytherapy has encouraged the development of advanced applicators and given rise to the growth of individualised 3D printing to achieve reproducible and predictable implants. These advances increase the quality of implants to better direct radiation to target volumes while sparing normal tissue. Applicator reconstruction has moved beyond manual digitising, to drag and drop of three-dimensional applicator models with embedded pre-defined source pathways, ready for auto-recognition and automation. The simplified TG-43 dose calculation formalism directly linked to reference air kerma rate of high-energy sources in the medium water remains clinically robust. Model-based dose calculation algorithms accounting for tissue heterogeneity and applicator material will advance the field of brachytherapy dosimetry to become more clinically accurate. Improved dose-optimising toolkits contribute to the real-time and adaptive planning portfolio that harmonises and expedites the entire image-guided brachytherapy process. Traditional planning strategies remain relevant to validate emerging technologies and should continue to be incorporated in practice, particularly for cervical cancer. Overall, technological developments need commissioning and validation to make the best use of the advanced features by understanding their strengths and limitations. Brachytherapy has become high-tech and modern by respecting tradition and remaining accessible to all.
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Braquiterapia , Neoplasias do Colo do Útero , Feminino , Humanos , Braquiterapia/métodos , Radiometria , Imageamento por Ressonância Magnética , Algoritmos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem RadioterapêuticaRESUMO
Our contribution focuses on the question of how aging subjects experience and interpret biographic transitions into old age - specifically against the background of the current sociodiscursive revaluation of the so-called young old. The results of our qualitative interviews with elderly men and women in Germany indicate that the self-description "young elderly" does not play a role in identity-building in higher age, although norms of "active" or "productive aging" are widely accepted by the elderly. On the other hand, notions of "very old age" in need of care appear as something that can barely be integrated into the self-concepts and life plans of the interviewees. The transition from adulthood into the "third" (i.e., old age) stage is, thus, subjectively being postponed by elderly people into the (imagined) very last stage of their lives.
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Envelhecimento/psicologia , Atitude Frente a Saúde , Avaliação Geriátrica/estatística & dados numéricos , Autoimagem , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Alemanha/epidemiologia , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Valores de Referência , Inquéritos e Questionários , Adulto JovemRESUMO
Our contribution focuses on the question of how aging subjects experience and interpret biographic transitions into old age - specifically against the background of the current sociodiscursive revaluation of the so-called young old. The results of our qualitative interviews with elderly men and women in Germany indicate that the self-description "young elderly" does not play a role in identity-building in higher age, although norms of "active" or "productive aging" are widely accepted by the elderly. On the other hand, notions of "very old age" in need of care appear as something that can barely be integrated into the self-concepts and life plans of the interviewees. The transition from adulthood into the "third" (i.e., old age) stage is, thus, subjectively being postponed by elderly people into the (imagined) very last stage of their lives.
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Envelhecimento/psicologia , Acontecimentos que Mudam a Vida , Preconceito , Autoimagem , Estereotipagem , Adaptação Psicológica , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Dependência Psicológica , Pessoas com Deficiência/psicologia , Feminino , Alemanha , Humanos , Entrevista Psicológica , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Desejabilidade Social , Identificação SocialRESUMO
Radiotherapy and brachytherapy are the definitive treatments for locally advanced cervix cancer. The use of soft-tissue imaging, particularly magnetic resonance imaging, has enhanced their effectiveness and improved clinical outcomes. However, the use of magnetic resonance imaging is largely restricted to well-resourced centres in both the first and developing world and remains elusive to many less advantaged centres, particularly those in areas with a high burden of cervix cancer. Ultrasound is an accessible, affordable and accurate imaging modality that can be used throughout the brachytherapy procedure. Ultrasound is primarily used to ensure safe insertion of the applicator but can also be used to guide planning. The methods used to utilise ultrasound images for planning are described. Ultrasound is particularly useful as a verification aid to confirm applicator placement after patients are moved and transferred around the radiotherapy department. It can also be used to verify the dimensions of treatment volumes over the course of brachytherapy. There is a crucial unmet need for an accessible economical soft-tissue imaging modality in cervical brachytherapy. Ultrasound has the potential to meet this need.
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Braquiterapia , Neoplasias do Colo do Útero , Feminino , Humanos , Ultrassonografia , Ultrassonografia de Intervenção , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapiaRESUMO
Using a cyanide model to induce neurotoxic effects in rat brain homogenates, we examined the neuroprotective properties of three H3 antagonists, namely clobenpropit, thioperamide and impentamine, and compared them to aspirin, a known neuroprotective agent. Superoxide anion levels and malondialdehyde concentration were assessed using the nitroblue tetrazolium and lipid peroxidation assays. Clobenpropit and thioperamide significantly reduced superoxide anion generation and lipid peroxidation. Impentamine reduced lipid peroxidation at all concentrations used, but only reduced superoxide anion generation at a concentration of 1 mM. In the lipid peroxidation assay, all the drugs compared favourably to aspirin. This study demonstrates the potential of these agents to be neuroprotective by exerting antioxidant effects.
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Encéfalo/efeitos dos fármacos , Agonistas dos Receptores Histamínicos/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/tratamento farmacológico , Superóxidos/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Aspirina/farmacologia , Encéfalo/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , Malondialdeído/antagonistas & inibidores , Piperidinas/farmacologia , Cianeto de Potássio/efeitos adversos , Ratos , Ratos Wistar , Receptores Histamínicos H3/efeitos dos fármacos , Tioureia/análogos & derivados , Tioureia/farmacologiaRESUMO
Progress has been made in the delivery of brachytherapy, from low-dose rate (LDR) to high-dose rate (HDR) treatments, allowing for dose optimisation, conformal treatments, improved radiation protection, and improved accuracy and efficiency. Image-guided brachytherapy, incorporating spatial and temporal changes, is now possible with advanced imaging and treatment technology. This report reviews the evidence for the benefits of image-guided brachytherapy using magnetic resonance imaging (MRI), mainly for cervix and prostate cancer, but also possibilities for other tumour sites. It also emphasises the need for a dedicated MRI unit for brachytherapy.
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Braquiterapia/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias/patologia , Neoplasias/radioterapia , Radioterapia Assistida por Computador/métodos , Humanos , PrognósticoRESUMO
INTRODUCTION: A 2005 survey of practices indicated limited use of three-dimensional (3D) imaging modalities and planning methods in cervix cancer brachytherapy in Australia and New Zealand. However, advancing technologies and published recommendations are influencing change. This survey aims to identify both changes in practice and awareness and uptake of Groupe European de Curietherapie of the European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) recommendations. METHODS: A survey was emailed to all radiotherapy departments with brachytherapy facilities. Twenty departments practise brachytherapy for cancer of the cervix. The survey consisted of five questions enquiring about use and type of 3D imaging; rate of reimaging and replanning; and contouring, prescribing and reporting practices. RESULTS: A 100% response rate was obtained. Sixty-five per cent of departments use 3D CT imaging to plan brachytherapy insertions. Thirty per cent of departments use two-dimensional (2D) x-rays. Four departments (20%) use a combination of imaging modalities including CT, ultrasound and MRI. Sixty-five per cent of departments reimage and replan for each insertion. Four departments (20%) contour, prescribe dose and report treatment according to GEC-ESTRO recommendations. CONCLUSIONS: There has been a marked increase in the use of 3D imaging and awareness of GEC-ESTRO recommendations. Implementation and reporting of image-based gynaecological brachytherapy is strongly dependent on local resources and infrastructure.
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Braquiterapia/métodos , Pesquisas sobre Atenção à Saúde/métodos , Imageamento Tridimensional/métodos , Guias de Prática Clínica como Assunto , Neoplasias do Colo do Útero/radioterapia , Austrália , Braquiterapia/estatística & dados numéricos , Feminino , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Humanos , Nova Zelândia , Planejamento da Radioterapia Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Sociedades MédicasRESUMO
This report describes the evolving use of transabdominal ultrasound (TAUS) as an imaging tool to verify tandem placement, localize the treatment volume and aid conformal brachytherapy planning for both cervical and uterine corpus cancers. Two patients, one with cancer of the cervix and one with cancer of the endometrium, are used as examples to illustrate the advantages of using TAUS. TAUS is used to guide applicator insertion and check the applicator in the treatment position. The dimensions of the uterus are recorded. Brachytherapy isodose plans are generated based on these measurements. Confirmation of uterine dimensions and isodose coverage is obtained using MRI taken after the initial fraction of treatment has been delivered. We illustrate how TAUS is successfully used to correct and verify tandem placement after the patient has been moved from insertion to treatment position. We also show how to use TAUS for conformal planning, based on individually derived target dimensions. TAUS has successfully been used to conformally plan treatment to the uterus and cervix, minimizing brachytherapy-related toxicity to surrounding structures. Ultrasound is portable, inexpensive and simple to use and allows for accurate, conformal, reproducible and adaptive treatments.
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Braquiterapia/métodos , Colo do Útero/diagnóstico por imagem , Neoplasias do Endométrio/radioterapia , Endométrio/diagnóstico por imagem , Radioterapia Conformacional/métodos , Neoplasias do Colo do Útero/radioterapia , Idoso , Braquiterapia/efeitos adversos , Colo do Útero/patologia , Endométrio/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Radiografia , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Ultrassonografia de Intervenção/métodosRESUMO
Establishing guidelines for the practice of brachytherapy throughout Australia and New Zealand is one of the goals of the Australasian Brachytherapy Group. To better appreciate Australasian resources and conditions, the group conducted a survey in early 2005. The aims were to survey current practices, to emphasize variations in practice and to determine the availability of advanced imaging and treatment methods to assess resources. A survey was sent to all Australian and New Zealand radiotherapy departments. The survey requested details of treatment with respect to external beam radiotherapy, brachytherapy, optimization methods, reporting methods, scheduling brachytherapy and access to imaging and methods of work-up. Thirty-four departments were contacted with 27 (79%) responses returned. Twenty-one departments use brachytherapy. Doses and fractionation schedules varied and use of sectional imaging was minimal. Individualized dosimetry is practised in a limited fashion by 60% of the surveyed departments. There is high compliance with International Commission on Radiation Units 38 dose reporting recommendations. All brachytherapy units identified have access to CT and 85% to MRI within the hospital settings. Brachytherapy for cancer of the cervix is, currently, largely based on the Manchester system. The survey did emphasize considerable variation in dose and fractionation schemes between departments. The Australasian Brachytherapy Group subgroup intends to proceed with the process of formulating recommendations for cervix brachytherapy. It is intended that these will cover the use of image-based planning and treatment, target definition(s), verification of brachytherapy treatments and a uniform dose-reporting mechanism.
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Braquiterapia/estatística & dados numéricos , Pesquisas sobre Atenção à Saúde , Padrões de Prática Médica/estatística & dados numéricos , Radioterapia (Especialidade)/estatística & dados numéricos , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/radioterapia , Austrália/epidemiologia , Feminino , Humanos , Nova Zelândia/epidemiologia , Neoplasias do Colo do Útero/diagnósticoRESUMO
We report VLA detections at 1.3, 2, and 3.6 cm of the Egg Nebula, RAFGL 2688. We resolve the source and find an inner 9&arcsec; diameter core that is produced by approximately 0.01 M middle dot in circle of dust. It seems that the Egg Nebula experienced a major mass ejection, losing approximately 1 M middle dot in circle during the past =1200 yr. The centimeter-wavelength emission is extended at a position angle of 53 degrees, while the famous jets and lobes in the Egg Nebula lie along a position angle of 15 degrees. The multiple symmetries in the Egg Nebula may occur because the rotation axis of the mass-losing star is not perpendicular to the orbital plane of the putative close binary. Between 3.6 cm and 350 µm, the dust opacity appears to vary as nu0.6, which can be explained if there are some grains with sizes at least as large as 0.5 cm.
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A range of N-substituted isoindolin-1-ones was prepared and their potential as novel antimicrobial agents was investigated. MIC values for active compounds were determined and reported.